CNN Money: Top business headlines for July 16

NEW YORK (CNN) -- CNN Money's Maribel Aber has your top business and financial news on this Tuesday, July 16.

Femtocell hack reveals mobile phones' calls, texts and photosAn increasingly popular technology for extending cell-phone coverage ranges had a major security hole that went undetected for years, through which an attacker could eavesdrop on everything a target did on their phone, according to new research released on Monday. The research brings to light previously unknown vulnerabilities in some models of femtocells, devices that mobile network operators use to bring wireless service to low-coverage zones. The compact boxes, which are typically as small as a standard cable modem, can be deployed in hard-to-reach spots like the top of an apartment building or a home in the mountains. Femtocells are also referred to as "network extenders," and analysts project that as many as 50 million of them will be in use by 2014.

Scamming Obamacare harder than you think
The way some people have interpreted the latest Obamacare rule change, you'd think the administration was inviting people to steal from the government. Officials announced on July 5 that insurance exchanges could relax how they verify the income of people who apply for federal financial help in the first year. But experts say the temporary change won't necessarily make it easier to scam the system. The subsidies at issue are meant to help people who can't afford to pay full freight for health insurance. Generally speaking, the less you make, the bigger the subsidy you get.

How one year of Marissa Mayer has changed Yahoo
Yahoo CEO Marissa Mayer likes to shop. During Mayer's one-year tenure -- her start date was a year ago Wednesday -- Yahoo has bought an incredible 16 startups. And she didn't even start the buying spree until she'd been CEO for three months. Since then Yahoo's acquisitions have been made at a breakneck pace, with the company sometimes announcing two purchases in a single day, or six over the course of a month. "It is just astounding how truly active Yahoo has been on the M&A front," said S&P Capital equity analyst Scott Kessler. "They're mostly buying very small companies, but still -- I don't know that any other company has matched this pace of buying." Mayer was likely inspired by her former employer Google, which often buys small companies in order to gain talented staffers.

Gas prices rise 14 cents over last week
Gas prices have jumped nearly 14 cents since last week as crude oil supplies dropped and political unrest in Egypt spurred worries about disruptions in supplies. Nationwide, a gallon of regular gas now costs an average of $3.61, up from $3.47 a week ago, according to the AAA Fuel Gauge Report. It was up 1 cent from Sunday. In California, the average price rose 4 cents a gallon to $4.02 from $3.98 a week ago. Experts say the price could climb even higher in the coming weeks as Americans hit the road on summer vacations. Companies are increasing production in the U.S. through new drilling techniques, including fracking, that have enabled the country to tap previously unreachable energy sources and meet 89% of its own energy needs in March.